Apparatus and method for photolithography with phase conjugate optics

• US 4,496,222 A
• Filed: 05/01/1984
• Issued: 01/29/1985
• Est. Priority Date: 12/21/1981
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Shah, Rajiv R.
• Primary Examiner(s): Punter, William H.
• Application Number:
  US06/605,984
• Time in Patent Office: 273 Days
• Field of Search: 350/3.62, 350/354, 350/393, 350/379, 355/77, 307/425
• US Class Current: 359/300
• CPC Class Codes: G02F 1/3538 for optical phase conjugation controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation using optical phase conjugation H01S3/10076
• CPC Class Codes: G03F 7/70216 Mask projection systems

Abstract

An apparatus and method of photolithography with phase conjugate optics having a pump nonlinear medium for producing four way mixing of a beam of coherent electromagnetic radiation incident to said nonlinear medium with a spatically modulated representation of image thereon. The nonlinear medium producing by the phenomenon of four way mixing. A phase conjugated beam having a representation of the image spatically amplitude modulated thereon. The phase conjugated beam is directed toward a surface sensitive to electromagnetic radiation.

Claims

1. A system for producing a reduced image on a surface sensitive electromagnetic radiation comprising:

(a) an emitting device producing a beam of coherent electromagnetic radiation;

(b) a beam splitter incident to said beam separating said beam into a power beam and an imaging beam;

(c) a mask incident to said imaging beam with said original image thereon to amplitude modulate said imaging beam to form an imaged beam;

(d) a convergence device incident to said power beam to produce a converging power beam;

(e) a divergence device incident to said converging power beam to produce a diverging power beam being collinear and coextensive with said converging power beam;

(f) a nonlinear medium incident to said converging power beam, said diverging power beam, and said imaged beam to produce a phase conjugated beam; and

(g) a target object having said surface disposed thereon incident to said phase conjugated beam producing a reduced image.

2. A method for producing a reduced image on a surface sensitive to electromagnetic radiation comprising the steps of:

(a) directing a converging power beam of coherent electromagnetic energy of a certain frequency through a nonlinear medium;

(b) directing a diverging power beam collinear and coextensive with said converging beam of said certain frequency into said nonlinear medium;

(c) directing an image beam of coherent electromagnetic energy with an amplitude modulated representation of said image thereon into said nonlinear medium to produce a converging phase conjugated imaged beam of coherent electromagnetic radiation with a representation of said image thereon; and

(d) directing said phase conjugated imaged beam onto said surface producing a reduced image.

3. An optical apparatus for a phase conjugated imaging system having a source of coherent electromagnetic energy directed in a beam along a first optical path and a nonlinear medium comprising:

(a) a beam splitter positioned along said first optical path to separate said beam into a power beam directed along said first optical path and an imaging beam directed along a second optical path;

(b) a converging device incident to said power beam along said first optical path directing a converging power beam through said nonlinear medium along said first optical path;

(c) a diverging device incident to said converging power beam directing a diverging power beam collinear and coextensive with said converging power beam along said first optical path into said nonlinear medium;

(d) a mask with a representation of said image thereon incident to said imaging beam along said second optical path for producing an imaged beam having an amplitude modulated representation of said image thereon directed along said second optical path into said nonlinear medium; and

(e) a beam splitter positioned along said second optical path intermediate said mask and said nonlinear medium for passing said image beams therethrough and directing along a third optical path a phase conjugated image beam from said nonlinear medium incident thereto received along said second optical path.

4. A system for producing a reduced image on a surface sensitive to electromagnetic radiation comprising:

(a) an emitting device producing a beam of coherent electromagnetic radiation;

(b) a beam splitter incident to said beam separating said beam into a power beam and an imaging beam;

(c) a mask incident to said imaging beam with said original image thereon to amplitude modulate said imaging beam to form an imaged beam;

(d) a diverging device incident to said power beam to produce a diverging power beam;

(e) a converging device incident to said converging power beam to produce a converging power beam collinear and coextensive with said diverging power beam;

(f) a nonlinear medium incident to said converging power beam, said diverging power beam, and said imaged beam to produce a phase conjugated beam; and

(g) a target object having said surface disposed thereon incident to said phase conjugated beam producing a reduced image.